Method and apparatus for fixing a graft in a bone tunnel

ABSTRACT

A method for fixing a portion of a piece of tissue in a bone tunnel comprising the steps of placing the portion of a piece of tissue in the bone tunnel, advancing spaced-apart first and second metal wires though the bone, transversely of the bone tunnel, so as to intersect the bone tunnel and extend into the portion of a piece of tissue, removing one of the wires and replacing the one removed wire with a first rod, and removing the other of the wires and replacing the other removed wire with a second rod, whereby to retain the portion of a piece of tissue in the bone tunnel with the rods.

This is a division of pending prior U.S. application Ser. No.09/015,493, filed Jan. 28, 1998 by Daniel J. McKernan et al. for “MethodAnd Apparatus For Fixing A Graft In A Bone Tunnel” now U.S. Pat. No.6,066,173.

FIELD OF THE INVENTION

This invention relates to surgical methods and apparatus in general, andmore particularly to methods and apparatus for fixing bone blocks inbone tunnels.

BACKGROUND OF THE INVENTION

The complete or partial detachment of ligaments, tendons and/or othersoft tissues from their associated bones within the body are relativelycommonplace injuries. Tissue detachment may occur as the result of anaccident such as a fall, overexertion during a work-related activity,during the course of an athletic event, or in any one of many othersituations and/or activities. Such injuries are generally the result ofexcess stress being placed on the tissues.

In the case of a partial detachment, commonly referred to under thegeneral term “sprain”, the injury frequently heals itself, if givensufficient time, and if care is taken not to expose the injury to unduestress during the healing process. If, however, the ligament or tendonis completely detached from its associated bone or bones, or if it issevered as the result of a traumatic injury, partial or permanentdisability may result. Fortunately, a number of surgical proceduresexist for re-attaching such detached tissues and/or completely replacingseverely damaged tissues.

One such procedure involves the re-attachment of the detached tissueusing “traditional” attachment devices such as staples, sutures and/orcancellous bone screws. Such traditional attachment devices have alsobeen used to attach tendon or ligament grafts (often formed fromautogenous tissue harvested from elsewhere in the body) to the desiredbone or bones.

Another procedure is described in U.S. Pat. No. 4,950,270, issued Aug.21, 1990 to Jerald A. Bowman et al. In this procedure, the damagedanterior cruciate ligament (“ACL”) in a human knee, for example, isreplaced by first forming bone tunnels through the tibia and femur atthe points of normal attachment of the anterior cruciate ligament. Next,a ligament graft with a bone block on one of its ends is sized so as tofit within the bone tunnels. Suture is then attached to the bone blockand thereafter passed through the tibial and femoral bone tunnels. Thebone block is then drawn through the tibial tunnel and up into thefemoral tunnel using the suture. As this is done, the graft ligamentextends back out of the femoral tunnel, across the interior of the kneejoint, and then through the tibial tunnel. The free end of the graftligament resides outside the tibia, at the anterior side of the tibia.Next, a bone screw is inserted between the bone block and the wall offemoral bone tunnel so as to securely lock the bone block in position bya tight interference fit. Finally, the free end of the graft ligament issecurely attached to the tibia.

In U.S. Pat. No. 5,147,362, issued Sep. 15, 1992 to E. Marlowe Goble,there is disclosed a procedure wherein aligned femoral and tibialtunnels are formed in a human knee. A bone block with a graft ligamentattached thereto is passed through the tunnels to a blind end of thefemoral tunnel where the block is fixed in place by an anchor. Theligament extends out the tibial tunnel, and the end thereof is attachedto the tibial cortex by staples or the like. Alternatively, the end ofthe ligament may be fixed in the tibial tunnel by an anchor or by aninterference screw.

Various types of ligament and/or suture anchors, and anchors forattaching other objects to bone, are also well known in the art. Anumber of these devices are described in detail in U.S. Pat. Nos.4,898,156; 4,899,743; 4,968,315; 5,356,413; and 5,372,599, each of whichis presently owned by Mitek Surgical Products, Inc. of Westwood, Mass.,the assignee of this patent application.

One known method for anchoring bone blocks in bone tunnels is through“cross-pinning”, in which a pin, screw or rod is driven into the bonetransversely to the bone tunnel so as to intersect the bone block andthereby cross-pin the bone block in the bone tunnel. In order to providefor proper cross-pinning of the bone block in the bone tunnel, a drillguide is generally used. The drill guide serves to ensure that thetransverse passage is positioned in the bone so that it will intersectthe appropriate tunnel section and the bone block. Drill guides for usein effecting such transverse drilling are shown in U.S. Pat. Nos.4,901,711; 4,985,032; 5,152,764; 5,350,380; and 5,431,651.

Other patents in which cross-pinning is discussed include U.S. Pat. Nos.3,973,277; 5,004,474; 5,067,962; 5,266,075; 5,356,435; 5,376,119;5,393,302; and 5,397,356.

In U.S. Pat. No. 5,431,651, issued Jul. 11, 1995 to E. Marlowe Goble, itis said that a cross-pin screw may be formed out of a material which maybe absorbed by the body over time, thereby eliminating any need for thecross-pin screw to be removed in a subsequent surgical procedure.

However, such absorbable cross-pin screws as are presently known in theart lack sufficient strength to be passed directly into the bone and thebone block. Accordingly, to use absorbable cross-pin screws, one mustfirst drill a hard metal drilling implement into the bone and boneblock, remove the drilling implement, and then replace the drillingimplement with the absorbable cross-pin screw. However, removal of thehard metal drilling implement often permits the bone block to shift inthe tunnel, such that the subsequent insertion of the absorbablecross-pin screw becomes impossible.

Accordingly, there exists a need for a method and apparatus for fixing abone block in a bone tunnel such that upon completion of the procedure,the bone block is cross-pinned in the bone tunnel by elements which aremade of absorbable material.

OBJECTS OF THE INVENTION

The object of the present invention is, therefore, to provide a methodfor fixing a bone block in a bone tunnel such that the bone block isretained in the tunnel by cross-pins which are made of a material whichis absorbable by the body.

A further object of the present invention is to provide devices by whichthe aforementioned method may be realized.

SUMMARY OF THE INVENTION

These and other objects of the present invention are addressed by theprovision and use of a novel method and apparatus for fixing a boneblock in a bone tunnel.

In one form of the invention, the novel method comprises the steps ofplacing the bone block in the bone tunnel, and then advancingspaced-apart first and second drill means through the bone transverselyof the bone tunnel so as to intersect the bone block and extendtherethrough. The method further includes the steps of removing one ofthe drill means and replacing the one removed drill means with a firstabsorbable rod, and then removing the other of the drill means andreplacing the other removed drill means with a second absorbable rod,whereby the bone block will be retained in the bone tunnel with theabsorbable rods. In one form of the invention, the first and seconddrill means may comprise metal wires.

The objects of the present invention are further addressed by theprovision and use of an alternative method for fixing a bone block in abone tunnel. The method comprises the steps of placing the bone block inthe bone tunnel, and then advancing spaced-apart first and second trocarand sleeve assemblies through the bone, transversely of the bone tunnel,so as to intersect the bone block and extend therethrough, the trocar ineach of the assemblies being disposed within one of the sleeves of theassemblies and substantially filling the sleeve. The method furtherincludes the steps of removing the trocar from the first of the sleeves,advancing a first absorbable rod through the first sleeve and throughthe bone block, and then removing the first sleeve, so as to leave thefirst absorbable rod in the bone and the bone block. The method furtherincludes the steps of removing the trocar from the second of thesleeves, advancing a second absorbable rod through the second sleeve andthrough the bone block, and then removing the second sleeve, so as toleave the second absorbable rod in the bone and the bone block, wherebythe bone block will be retained in the bone tunnel with the absorbablerods.

The objects of the present invention are further addressed by theprovision and use of another alternative method for fixing a bone blockin a bone tunnel. The method comprises the steps of placing the boneblock in the bone tunnel, and then advancing spaced-apart first andsecond trocar and sleeve assemblies through the bone transversely of thebone tunnel so as to intersect the bone block and extend therethrough,the trocar in each of the assemblies being disposed within one of thesleeves of the assemblies and substantially filling the sleeve. Themethod further includes the steps of removing the trocar from thesleeves, advancing absorbable rods through the sleeves and through thebone block, and then removing the sleeves from the bone block and thebone, so as to leave the absorbable rods in the bone block and the bone,whereby the bone block will be retained in the bone tunnel with theabsorbable rods.

In accordance with a further feature of the present invention, there isprovided a rack assembly for cross-pinning a bone block in a bone tunnelin a human femur, the rack assembly comprising an L-shaped member havinga base portion and an arm portion extending transversely of the baseportion, and a cannulated sleeve for movement through a tibia and intothe femur and for disposition in the femoral bone tunnel, the cannulatedsleeve having an enlarged head portion at a free end thereof fordisposition in the bone tunnel in the femur and being connectable to thebase portion of the L-shaped member at an opposite end thereof. The rackassembly further includes a trocar sleeve guide member removablyconnectable to the arm portion of the L-shaped member and having boresextending therethrough at an angle normal to a longitudinal axis of thecannulated sleeve's head portion, first and second trocar sleeves formovable disposition in the bores, respectively, and at least one trocarfor disposition in the trocar sleeves, the trocar being interconnectablewith the trocar sleeve in which the trocar is disposed such that thetrocar sleeve and the trocar therein are movable axially toward thecannulated sleeve's head portion and rotatable together, such that theinterconnected trocar and trocar sleeve are adapted for drilling intothe femur and the bone block. The trocar is removable from the trocarsleeves, and absorbable rods are provided for sliding through the trocarsleeves and through the bone block, the trocar sleeves being removablefrom the bone block and the femur and from the absorbable rods, so as toleave the absorbable rods in the bone block and the femur.

In accordance with a still further feature of the present invention,there is provided another rack assembly for cross-pinning a bone blockin a bone tunnel in a human femur. The rack assembly comprises anL-shaped member having a base portion and an arm portion extendingtransversely of the base portion, and a cannulated sleeve for movementthrough the femur until a free end thereof is disposed adjacent to thebone block, with an opposite end thereof being connectable to the baseportion of the L-shaped member. A trocar sleeve guide member isremovably connectable to the arm portion of the L-shaped member and isprovided with bores extending therethrough at an angle normal to ahypothetical extension of a longitudinal axis of the cannulated sleeve.First and second trocar sleeves are provided for movable disposition inthe bores, respectively. At least one trocar is provided for dispositionin the trocar sleeves, the trocar being interconnectable with the trocarsleeve in which the trocar is disposed such that the trocar sleeve andthe trocar therein are movable axially toward the bone block androtatable together, such that the interconnected trocar and trocarsleeve are adapted for drilling into the femur and the bone block. Thetrocar is removable from the trocar sleeves, and absorbable rods areslidable through the trocar sleeves and through the bone block, thetrocar sleeves being removable from the bone block and the femur andfrom the absorbable rods so as to leave the absorbable rods in the boneblock and the femur.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone, the method comprising the steps of:

placing the portion of a piece of tissue in the bone tunnel;

advancing spaced-apart, first and second drill means through the bonetransversely of the bone tunnel so as to intersect and extend into thetissue;

removing one of the drill means and replacing the one removed drillmeans with a first rod; and

removing the other of the drill means and replacing the other removeddrill means with a second rod;

whereby to retain the portion of a piece of tissue in the bone tunnelwith the rods.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone, the method comprising the steps of:

placing the portion of a piece of tissue in the bone tunnel;

advancing a first drill means through a first portion of the bone andtransversely of the tunnel so as to intersect and extend into theportion of a piece of tissue;

advancing a second drill means through a second portion of the bone andtransversely of the tunnel so as to intersect and extend into theportion of a piece of tissue, the second drill means being spaced fromthe first drill means;

removing one of the first and second drill means while leaving the otherof the first and second drill means in place in the bone and the portionof a piece of tissue;

advancing a first rod through a bore left by removal of the one drillmeans, such that the first rod extends through the bone and into theportion of a piece of tissue;

removing the other of the first and second drill means; and

advancing a second rod through a bore left by removal of the other drillmeans, such that the second rod extends through the bone and into theportion of a piece of tissue;

whereby to retain the portion of a piece of tissue in the bone tunnelwith the rods.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone, the method comprising the steps of:

(a) placing the portion of a piece of tissue in the bone tunnel;

(b) advancing a plurality of drill means through the bone transverselyof the tunnel so as to intercept and extend into the portion of a pieceof tissue;

(c) removing at least one of the drill means while leaving at least oneof the drill means in place, and replacing the removed at least onedrill means with at least one rod;

(d) removing at least one further of the drill means and replacing theat least one further of the drill means with at least one further rod;and

(e) repeating step (d), if and as desired, until a selected number ofthe drill means each is replaced by a rod,

whereby to retain the portion a piece of tissue in the bone tunnel withthe rods.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue tunnel in a bone, themethod comprising the steps of:

placing a portion of a piece of tissue in the bone tunnel;

advancing spaced-apart, first and second trocar and sleeve assembliesthrough the bone transversely of the bone tunnel so as to intersect andextend into the portion of a piece of tissue, the trocar in each of theassemblies being disposed within one of the sleeves of the assembliesand substantially filling the sleeve;

removing the trocar from the first of the sleeves, advancing a first rodthrough the first sleeve and into the portion of a piece of tissue, andthen removing the first sleeve, so as to leave the first rod in the boneand the portion of a piece of tissue; and

removing the trocar from the second of the sleeves, advancing a secondrod through the second sleeve and into the portion of a piece of tissue,and then removing the second sleeve, so as to leave the second rod inthe bone and the portion of a piece of tissue,

whereby to retain the portion of a piece of tissue in the tunnel withthe rods.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone, the method comprising the steps of:

placing a portion of a piece of tissue in the bone tunnel;

advancing spaced-apart, first and second trocar and sleeve assembliesthorough the bone transversely of the bone tunnel so as to intersect andextend into the portion of a piece of tissue, the trocar in each of theassemblies being disposed within one of the sleeves of the assembliesand substantially filling the sleeve;

removing the trocar from the sleeves;

advancing rods through the sleeves and into the portion of a piece oftissue; and

removing the sleeves from the portion of a piece of tissue and the boneand the rods so as to leave the rods in the portion of a piece of tissueand the bone,

whereby to retain the portion of a piece of tissue in the tunnel withthe rods.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone covered by skin, the method comprising the steps of:

placing the portion of a piece of tissue in the bone tunnel;

advancing a trocar and sleeve assembly through the skin and through thebone transversely of the bone tunnel so as to intersect the portion of apiece of tissue and extend at least partially therethrough, the trocarof the assembly being disposed within the sleeve of the assembly;

removing the trocar from the sleeve;

advancing a rod through the sleeve and through the skin and into theportion of a piece of tissue; and

removing the sleeve, so as to leave the rod in the bone and the portionof the piece of tissue, whereby to retain the portion of the piece oftissue in the bone tunnel.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone, the method comprising the steps of:

placing the portion of a piece of tissue in the bone tunnel;

advancing spaced-apart, first and second trocar and sleeve assembliesthrough skin covering the bone and through the bone transversely of thebone tunnel so as to intersect and extend into the portion of a piece oftissue, the trocar in each of the assemblies being disposed within oneof the sleeves of the assemblies and substantially filling the sleeve;

removing the trocar from the first of the sleeves, advancing a first rodthrough the first sleeve and into the portion of a piece of tissue, andthen removing the first sleeve, so as to leave the first rod in the boneand the portion of a piece of tissue; and

removing the trocar from the second of the sleeves, advancing a secondrod through the second sleeve into the portion of a piece of tissue, andthen removing the second sleeve, so as to leave the second rod in thebone and the portion of a piece of tissue,

whereby to retain the portion of a piece of tissue in the bone tunnelwith the rods.

In accordance with a further feature of the invention, there is provideda method for fixing a portion of a piece of tissue in a bone tunnel in abone, the method comprising the steps of:

advancing first and second spaced-apart drill means through the bonetransversely of the bone tunnel so as to intersect and permissiblyextend through the bone tunnel;

withdrawing the first and second spaced-apart drill means from the bonetunnel;

locating a portion of a piece of tissue in the bone tunnel in transversealignment with the paths of the first and second spaced-apart drillmeans through the bone;

advancing third and fourth spaced-apart drill means into, andpermissibly through, the portion of a piece of tissue;

removing the third of the drill means and replacing the third removeddrill means with a first rod; and

removing the fourth of the drill means and replacing the fourth of thedrill means with a second rod;

whereby to retain the portion of a piece of tissue in the bone tunnelwith the rods.

In accordance with a further feature of the invention, there is provideda rack assembly for cross-pinning a portion of a piece of tissue in abone tunnel extending through a first bone on one side of a skeletaljoint and into a second bone on the other side of the skeletal joint,the rack assembly comprising:

an L-shaped member having a base portion and an arm portion extendingtransversely of the base portion;

a cannulated sleeve for movement through the bone tunnel in the firstbone and into the bone tunnel in the second bone, the cannulated sleevehaving a head portion at a free end thereof for disposition in the bonetunnel in the second bone and being connectable to the base portion ofthe L-shaped member at an opposite end, the head defining a windowtherethrough oriented substantially parallel to the base portion of theL-shaped member when the cannulated sleeve is connected to the baseportion of thereof;

a trocar sleeve guide member removably connectable to the arm portion ofthe L-shaped member and having bores extending therethrough at an anglenormal to a projection of the longitudinal axis of the cannulatedsleeve;

first and second trocar sleeves for movable disposition in the bores,respectively;

at least one trocar for disposition in the trocar sleeves, the trocarbeing interconnectable with the trocar sleeve in which the trocar isdisposed, the trocar sleeve and the trocar therein being movable axiallytoward the head portion of the cannulated sleeve and rotatable togethersuch that the interconnected trocar and trocar sleeve are adapted fordrilling into the second bone and at least the trocar is adapted topenetrate through the window in the head of the cannulated sleeve and aportion of a piece of tissue subsequently substituted therefore;

the trocar being removable from the trocar sleeves; and

the trocar sleeves being adapted to receive rods slidable through thetrocar sleeves and through the portion of a piece of tissue, the trocarsleeves being removable from the second bone and from the rods so as toleave the rods in the portion of a piece of tissue and the second bone.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention willbe more fully discussed in, or rendered obvious by, the followingdetailed description of the preferred embodiments of the invention,which is to be considered together with the accompanying drawingswherein like members refer to like parts, and further wherein:

FIG. 1 is a diagrammatical sectional view of a human knee joint, withappropriate bone tunnels formed therein and with a ligament bone blockdisposed in one of the tunnels;

FIG. 2 is similar to FIG. 1, but illustrative of a metal wire insertionphase of the inventive method;

FIG. 3 is similar to FIG. 2 but illustrative of completion of the metalwire insertion phase;

FIG. 4 is similar to FIG. 3, but illustrative of a first metal wirewithdrawal phase;

FIG. 5 is similar to FIG. 4, but illustrative of a first absorbable rodinsertion phase;

FIG. 6 is similar to FIG. 5, but illustrative of the first absorbablerod having been fully inserted;

FIG. 7 is similar to FIG. 6, but illustrative of a second metal wirewithdrawal phase;

FIG. 8 is similar to FIG. 7, but illustrative of a second absorbable rodinsertion phase;

FIG. 9 is similar to FIG. 8, but illustrative of the completion of theabsorbable rod insertion phase of the inventive method;

FIG. 10 is a side elevational view of one form of rack assembly forcross-pinning a bone block in a bone tunnel, illustrative of anembodiment of the invention;

FIG. 11 is a bottom view of the rack assembly of FIG. 10;

FIG. 12 is a bottom view of a trocar sleeve guide member portion of therack assembly of FIGS. 10 and 11;

FIG. 13 is a side elevational view of the trocar sleeve guide member;

FIG. 14 is a front elevational view of the trocar sleeve guide member;

FIG. 15 is an interrupted side elevational view of a trocar portion ofthe rack assembly of FIG. 10;

FIG. 16 is an interrupted side elevational view, broken away and partlyin section, of a trocar sleeve portion of the rack assembly of FIG. 10;

FIG. 17 is an end view of the trocar sleeve portion of FIG. 16;

FIG. 18 is a diagrammatical view of a human knee joint and illustrativeof a step in a method in which the rack assembly of FIG. 10 is used;

FIGS. 19-28 are diagrammatical views illustrating a series of steps inthe use of the rack assembly of FIG. 10;

FIG. 29 is a side elevational view of another form of rack assemblyillustrative of an alternative embodiment of the invention;

FIG. 30 is a bottom view of the rack assembly of FIG. 29;

FIG. 31 is a bottom view of a trocar sleeve guide member portion of therack assembly of FIG. 29;

FIG. 32 is a side elevational view of the trocar sleeve guide member;

FIG. 33 is a front elevational view of the trocar sleeve guide member;

FIG. 34 is a view similar to that of FIG. 18;

FIGS. 35-40 are diagrammatical views illustrating a series of steps inthe use of the rack assembly of FIG. 29;

FIG. 41 is a side elevational view of a graft ligament, tendon or thelike, wherein one end of the graft has been folded back upon itself andtack-stitched in place, and wherein a rod extending through the tissueis shown in phantom;

FIG. 42 is a side elevational view similar to FIG. 41, wherein the graftligament, tendon or the like has been folded back upon itself, andwherein a rod extending between adjacent folds of the graft is shown inphantom;

FIG. 43 is a side elevational view similar to FIG. 42, wherein thefolded tissue has been “whip stitched” together, and wherein a rodextending through the whip stitched tissue mass is shown in phantom;

FIGS. 44-51 are illustrative sectional side elevational views showingthe steps of advancing a trocar/trocar sleeve combination into a boneand through a bone tunnel therein, removing the trocar, inserting a rodinto the sleeve and across the bone tunnel, removing the sleeve, andpulling an end of a tissue graft around the rod located across the bonetunnel;

FIGS. 52 and 53 are illustrative side elevational views ofrepresentative bone blocks showing two possible examples of how a boneblock may fracture during or after the placement of a cross-pintherethrough;

FIG. 54 is an illustrative sectional side elevational view of a boneblock located in a partially closed ended bone tunnel and fixed inposition by a rod extending across the bone tunnel between the boneblock and the open end of the bone tunnel;

FIG. 55 is an illustrative side elevational view of an assembledtrocar/trocar sleeve assembly for use in the present invention;

FIGS. 56-63 are illustrative side sectional, elevational views showingthe use of long trocars inserted through sleeves, originally placed withthe combination depicted in FIG. 55, to penetrate the bone and a boneblock for the emplacement of rods to hold the bone block in place withinthe bone tunnel;

FIG. 64 is a side elevational view of a stepped trocar formed inaccordance with the present invention;

FIG. 65 is a side elevational, sectional view showing a trocar sleevehaving an internal stop adapted to limit the travel of a stepped trocar,as depicted in FIG. 64, therethrough;

FIG. 66 is an exploded, side sectional, elevational view illustratingthe use of a plunger and tapping device for driving a rod through asleeve in bone and into a bone block located in a bone tunnel;

FIG. 67 is a side elevational view of another trocar/trocar sleevecombination formed in accordance with the present invention;

FIG. 68 is a side elevational view of still another trocar/trocar sleevecombination formed in accordance with the present invention;

FIG. 69 is an illustrative perspective view showing an apertured headsubstituted for the enlarged cannulated sleeve head depicted in FIG. 19;and

FIGS. 70-74 are illustrative side elevational views showing thedisposition of a rod across a reduced bone fracture using atrocar/trocar sleeve combination formed in accordance with the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIG. 1, it will be seen that a human knee joint 10,including a femur 12 and tibia 14, has been provided with an appropriatefemoral bone tunnel 16 and an appropriate tibial bone tunnel 18. Suchtunnels may be provided in ways well known in the art. A bone block 20,having ligament material 22 attached thereto, has been positioned infemoral tunnel 16. Such bone block positioning may also be achieved inways well known in the art.

Looking next at FIG. 2, in accordance with the present invention, afirst metal wire 30, which may be of the type commonly referred to as aguidewire or a “K-wire”, is advanced through skin 31 and a first portion32 of femur 12. First wire 30 is advanced transversely of femoral tunnel16 so as to intersect and extend through bone block 20, as shown in FIG.2. Thereafter, or simultaneously therewith, a second metal wire 34 isadvanced through a second portion 36 of femur 12. Second wire 34 is alsoadvanced transversely of femoral tunnel 16 so as to also intersect andextend through bone block 20 (FIG. 3). At this point, bone block 20 issecurely held in femoral tunnel 16 by the two spaced-apart metal wires30, 34.

Referring next to FIG. 4, it will be seen that one of the two wires 30,34 is then removed, while the other of the two wires 30, 34 is left inplace in femur 12 and bone block 20. By way of example but notlimitation, wire 30 may be removed while wire 34 is left in place. Afirst absorbable rod 40 (FIG. 5) is then advanced through the bore 42left by the removal of first wire 30, such that first absorbable rod 40extends through femur 12 and bone block 20 (FIG. 6). At this point, boneblock 20 is securely held in femoral tunnel 16 by both metal wire 34 andfirst absorbable rod 40.

Thereafter, the other of the two metal wires 30, 34 is withdrawn (e.g.,in FIG. 7, metal wire 34 is removed), and a second absorbable rod 44(FIG. 8) is advanced through the bore 46 left by the removal of metalwire 34, such that second absorbable rod 44 also extends through femur12 and bone block 20 (FIG. 9).

It will be appreciated that, upon completion of the insertion of secondabsorbable rod 44 (FIG. 9), bone block 20 is retained in femoral tunnel16 solely by the absorbable rods 40, 44.

The absorbable rods 40, 44 may be made out of a material such aspolylactic acid (PLA), polyglycolic acid (PGA), polydiaxanone (PDS), orout of some other such material which is formable into a relativelyrigid and hard configuration, but which is absorbable by the body of thepatient over time. If desired, the distal ends of absorbable rods 40, 44can be pointed or rounded so as to facilitate their deployment into thebody.

There is thus provided a method by which a bone block is fixed within abone tunnel, such that the bone block is anchored in the tunnel bycross-pins which are made out of a material which is absorbable by thebody over time.

It will be understood that while the above method has been described andillustrated with respect to first and second wires replaced serially byfirst and second absorbable rods, the method may be exercised with anyreasonable number of wires, exceeding one. In the latter instance, themethod includes the steps of placing the bone block in the bone tunnel,and then advancing a plurality of metal wires through the bone,transversely of the tunnel, so as to intercept the bone block and extendtherethrough. At least one of the wires is then removed while leaving atleast one of the wires in place, and that at least one removed wire isthen replaced by at least one absorbable rod. At least one further ofthe wires is then removed and that at least one removed wire is thenreplaced by at least one further absorbable rod. The last-mentioned stepis then repeated until a selected number of the metal wires is eachreplaced with an absorbable rod, whereby to retain the bone block in thebone tunnel with absorbable rods.

It will also be understood that while FIGS. 1-9 show metal wires 30, 34and absorbable rods 40, 44 passing completely through bone block 20during the cross-pinning procedure, it is also possible for metal wires30, 34 and absorbable rods 40, 44 to pass only part way across boneblock 20, if the same should be desired.

Furthermore, it will also be understood that while the above method hasbeen described and illustrated with respect to metal wires 30, 34 beingused to drill through femur 12 and bone block 20, other drillingimplements (e.g., a twist drill or a spade drill) might also be used.

As noted above, various drill guides have been developed for formingtransverse passages through the femur and bone block so as to cross-pinthe bone block within the femoral tunnel. If desired, the inventivemethod of the present invention may be practiced using such known drillguides. Alternatively, the present invention may also be practiced usinga novel rack assembly formed in accordance with the present invention.

More particularly, and looking now at FIGS. 10-17, a novel rack assembly50 is disclosed for practicing the present invention. Rack assembly 50comprises an L-shaped member 52 having a base portion 54 and an armportion 56. The arm portion 56 extends transversely, and preferably isnormal to, base portion 54.

Rack assembly 50 also includes a cannulated sleeve 58 which, at a firstend 60 thereof, is provided with an enlarged head portion 62, and which,at a second end 64 thereof, is releasably connectable to base portion 54of L-shaped member 52. Sleeve 58 may be retained in a bore 65 (FIG. 11)formed in base portion 54 by a set screw 66.

A trocar sleeve guide member 70 is removably connectable to arm portion56 of L-shaped member 52. Trocar sleeve guide member 70 is provided withbores 72 extending therethrough. Bores 72 extend substantially normal toa longitudinal axis 68 (FIG. 10) of the enlarged head portion 62 ofcannulated sleeve 58. A set screw 71 (FIG. 11) may be used to releasablyretain trocar sleeve guide member 70 in position on arm portion 56.Alternatively, or in addition, arm portion 56 may be provided with stopmeans (not shown) for limiting the movement of the trocar sleeve guidemember 70 along arm portion 56. Trocar sleeve guide member 70 ispreferably formed in two halves releasably held together by a set screw73 (FIG. 11), whereby trocar sleeve guide member 70 can be slidablymounted on, or detached from, trocar sleeves 74, 76 passing throughbores 72, as will hereinafter be discussed.

First and second trocar sleeves 74, 76 are slidably received by bores72, such that sleeves 74, 76 are axially and rotatably movable in bores72. Referring to FIGS. 16 and 17, it will be seen that trocar sleeve 74is provided with a collar portion 78 having a slot 80 formed therein.Sleeve 76 is substantially identical to sleeve 74.

Rack assembly 50 also includes one or more trocars 82 (FIGS. 10 and 15)for disposition in the sleeves 74, 76. Each trocar 82 is provided with asharp end 84 (FIG. 15) for penetration of bone. A transversely-extendingpin 86 is provided near (but spaced from) the opposite end of the trocar82. Pin 86 is fixed in place and is receivable by the slots 80 of trocarsleeves 74, 76 such that axial (in a distal direction) and rotationalmovement of trocar 82 causes similar movement of sleeves 74, 76.

The first and second absorbable rods 40, 44 are slidable through sleeves74, 76, as will be further described hereinbelow.

FIGS. 18-28 illustrate how rack assembly 50 may be used to practice thepresent invention.

Referring now to FIG. 18, there is shown a human knee joint 10 includingfemur 12 and tibia 14. An appropriate femoral tunnel 16 and anappropriate tibial tunnel 18 have been provided, as by means and methodswell known in the art. A guidewire 90 extends through the bone tunnels16, 18 as shown.

In accordance with the present invention, the rack assembly's cannulatedsleeve 58 is fed over guidewire 90, through tibial tunnel 18 and intofemoral tunnel 16, until the cannulated sleeve's head portion 62 engagesan annular shoulder 92 in femoral tunnel 16 (FIG. 19). As this occurs,guidewire 90 extends through a bore 94 (FIGS. 10 and 19) formed in baseportion 54 of L-shaped member 52. The cannulated sleeve's head portion62 is preferably sized so as to form a snug fit in femoral tunnel 16.Cannulated sleeve 58 may be positioned in the bone tunnels 16, 18 andthen connected to L-shaped member 52 or, more preferably, cannulatedsleeve 58 may be first connected to L-shaped member 52 and thenpositioned in femur 12 and tibia 14. Trocar sleeve guide member 70, ifnot already positioned on arm portion 56, is then fixed to arm portion56, as by set screw 71 (FIG. 11).

First trocar sleeve 74 is then inserted in a bore 72 of guide member 70(FIG. 20), and trocar 82 is extended through sleeve 74 until pin 86(FIG. 15) of trocar 82 is nested in slot 80 (FIGS. 16 and 17) of sleeve74, with the trocar's sharp end 84 extending beyond the distal end ofsleeve 74 (FIG. 20). Alternatively, trocar 82 may be mounted in firsttrocar sleeve 74 before first trocar sleeve 74 is mounted in a bore 72.The combination of trocar sleeve 74 and trocar 82 is then drilled, as aunit, into femur 12 toward, but short of, the enlarged head portion 62of cannulated sleeve 58 (FIG. 20).

Trocar 82 may then be withdrawn from first trocar sleeve 74 and placedin second trocar sleeve 76 (FIG. 21). Alternatively, a second trocar 82may be provided for second trocar sleeve 76. In either case, thecombination of trocar sleeve 76 and trocar 82 is then drilled, as aunit, into femur 12 toward, but short of, head portion 62 of cannulatedsleeve 58. The rack's L-shaped member 52 may then be removed from thesurgical site. This may be accomplished by first loosening set screw 73(FIG. 11) so as to separate trocar sleeve guide member 70 into its twohalves, whereby trocar sleeves 74, 76 will be freed from guide member70, and then sliding cannulated sleeve 58 downward along guidewire 90until the cannulated sleeve emerges from bone tunnels 16, 18. Thisprocedure will leave trocar sleeves 74, 76 lodged in femur 12 (FIG. 22).

Guidewire 90 is then used to pull a suture 96, which is attached to boneblock 20, up through tibial tunnel 18 and into femoral tunnel 16, untilbone block 20 engages the annular shoulder 92 in femoral tunnel 16 (FIG.23). Guidewire 90 may be provided with an eyelet (not shown) adjacent toits proximal end so as to facilitate this procedure. Bone block 20 canthen be held is this position by maintaining tension on the portion ofsuture 96 emerging from the top of femur 12.

Trocar sleeve 76 and trocar 82 are then drilled through bone block 20,as shown in FIG. 24. Trocar 82 may then be removed from sleeve 76,placed in sleeve 74, and sleeve 74 and trocar 82 drilled through boneblock 20, as shown in FIG. 25. The trocar 82 (or trocars 82 if more thanone trocar is used) may then be withdrawn from the sleeve 74 (or sleeves74, 76). The first absorbable rod 40 is then inserted, by sliding rod 40through trocar sleeve 74 into a position extending through bone block 20(FIG. 26). Sleeve 74 may then be withdrawn from bone block 20 and femur12, leaving first absorbable rod 40 in place in femur 12 and extendingthrough bone block 20, as shown in FIG. 27.

Similarly, second absorbable rod 44 is then slid into place throughsleeve 76. Sleeve 76 is then removed, leaving second absorbable rod 44,along with first absorbable rod 40, extending through bone block 20 soas to lock bone block 20 in place in femoral tunnel 16, as shown in FIG.28.

It should be appreciated that it is also possible to provide rackassembly 50 with a guide member 70 which is not formed in two separablehalves. In this situation, when the rack's L-shaped member 52 is to bewithdrawn from the surgical site (see FIGS. 21 and 22), guide member 70can simply be detached from L-shaped member 52 by unscrewing set screw71. Guide member 70 can then be left mounted on the outboard portions ofsleeves 74, 76 until sleeves 74, 76 are withdrawn from the surgicalsite, with guide member 70 being removed with the last of the sleeves74, 76.

The present invention may also be practiced using the novel rackassembly 100 illustrated in FIGS. 29-33. Rack assembly 100 comprises anL-shaped member 102 having a base portion 104 and an arm portion 106.Arm portion 106 extends transversely of, and preferably is normal to,base portion 104.

Rack assembly 100 also includes a cannulated sleeve 108 which, at a baseend 110 thereof, is connected to base portion 104. Cannulated sleeve 108may be retained in a bore 112 in base portion 104, as by screw threadsor a set screw (not shown) or a press fit or the like. Cannulated sleeve108 is provided with a slot 114 (FIG. 29) extending substantiallythroughout the length of sleeve 108. Base portion 104 of L-shaped member102 is also provided with a slot 116 (FIG. 30) which is alignable withthe sleeve's slot 114 so as to place the slots 114, 116 in communicationwith each other.

A trocar sleeve guide member 120 is removably connectable to arm portion106 of L-shaped member 102. Trocar sleeve guide member 120 is providedwith bores 122 extending therethrough. Bores 122 extend substantiallynormal to a hypothetical extension of the longitudinal axis 124 ofcannulated sleeve 108. A set screw 126 (FIG. 30) may be used toreleasably retain trocar sleeve guide member 120 in position on armportion 106. To assist in positioning trocar sleeve guide member 120 onarm portion 106 of L-shaped member 102, arm portion 106 may be providedwith a stop means (not shown) for limiting movement of member 120 on armportion 106. Trocar sleeve guide member 120 is preferably formed in twohalves releasably held together by a set screw 127 (FIG. 30), wherebytrocar sleeve guide member 120 can be slidably mounted on, or detachablefrom, trocar sleeves 128, 130 passing through bores 122, as willhereinafter be discussed.

First and second trocar sleeves 128, 130 are received by bores 122, suchthat sleeves 128, 130 are axially and rotatably movable in bores 122.The two trocar sleeves 128, 130 are substantially identical to is thesleeve 74 shown in FIGS. 16 and 17. Rack assembly 100 also includes oneor more trocars 132 for disposition in sleeves 128, 130. The trocar 132is substantially identical to the trocar 82 shown in FIG. 15. Theaforementioned first and second absorbable rods 40, 44 are slidablethrough sleeves 128, 130.

FIGS. 34-40 illustrate how rack assembly 100 may be used to practice thepresent invention.

Referring now to FIG. 34, it will be seen that bone tunnels 16 and 18are formed in femur 12 and tibia 18, respectively, and a guidewire 90extends through bone tunnels 16, 18. Guidewire 90 is then used to pull asuture 96, which is attached to bone block 20, up through tibial tunnel18 and into femoral tunnel 16, such that bone block 20 is in engagementwith annular shoulder 92 (FIG. 35). Bone block 20 is kept in thisposition by maintaining tension on the portion of suture 96 emergingfrom the top of femur 12.

Suture 96 is then introduced into the rack assembly's cannulated sleeve108 and base portion 104 by way of slots 114, 116. Cannulated sleeve 108is then passed down the hole 133 (FIGS. 35 and 36) left by the removedguidewire 90 until the distal end of the cannulated sleeve engages thetop end of bone block 20 (FIG. 36). Next, first trocar sleeve 128 isextended through a guide member bore 122 and a trocar 132 is insertedinto sleeve 128. Alternatively, a trocar 132 may be inserted into firsttrocar sleeve 128 before first trocar sleeve 128 is inserted into aguide member bore 122. The sleeve 128 and trocar 132 are then drilled,as a unit, into femur 12. With bone block 20 held against shoulder 92 bypulling on suture 96, the combination of sleeve 128 and trocar 132 isdrilled through bone block 20 (FIG. 36). In a similar manner, sleeve 130and trocar 132 (either the same trocar used with sleeve 128 or anothertrocar) are then drilled through bone block 20, as shown in FIG. 37.

L-shaped member 102 and cannulated sleeve 108 are then removed from thesurgical site. This may be accomplished by first loosening set screw 127(FIG. 30) so as to separate trocar sleeve guide member 120 into its twohalves, whereby trocar sleeves 128, 130 will be freed from guide member120, and then sliding cannulated sleeve 108 upward and out of hole 133.Any trocars 132 are then removed, leaving the trocar sleeves 128, 130extending into femur 12 and across bone block 20, as shown in FIG. 38.

Second absorbable rod 44 is then slid through sleeve 130 and sleeve 130removed (FIG. 39), and first absorbable rod 40 is slid through sleeve128 and sleeve 128 removed, leaving absorbable rods 40, 44 in place(FIG. 40) holding bone block 20 locked in femoral tunnel 16.

Suture 96 is then slipped through bone block 20 and removed, in themanner well known in the art.

It is to be understood that the present invention is by no means limitedto the application thereof as herein disclosed and/or as shown in thedrawings. For example, for illustrative purposes, the inventive methodand apparatus are described herein and illustrated with reference to thehuman knee joint. It is foreseen that the method and apparatus describedherein will be particularly beneficial with respect to such operations.However, it will also be appreciated by those skilled in the art thatthe method and apparatus described herein find utility with respect tomammals generally, and with respect to other bones as, for example, inshoulder joints or the like.

By way of further example, trocars 82 and 132 and their associatedsleeves 74, 76 and 128, 130, respectively, might be passed only part waythrough bone block 20, but not all the way through; or sleeves 74, 76and/or sleeves 128, 130 might be stopped short of bone block 20 whiletrocars 82 and/or 132 penetrate into bone block 20.

Furthermore, trocars 82 and 132 are disclosed herein as being in theform of a hard rod with a sharp tip for penetrating bone. Thus, forexample, trocars 82 and 132 might comprise guidewires or K-wires with apyramidal front point. Alternatively, however, the invention might alsobe practiced with trocars 82 and 132 comprising a twist drill, a spadedrill and/or some other sort of drill.

Also it is contemplated that trocars 82 and/or 132 might be used withtheir associated rack assemblies 50 and 100, respectively, but withouttheir associated sleeves 74, 76 and 128, 130, respectively. In thiscase, at least one trocar would always remain positioned in bone block20 until at least one absorbable rod 40, 44 was positioned in the boneblock.

It desired, it is also possible to practice the present invention usingjust one sleeve 74 and one trocar 82, or just one sleeve 76 and onetrocar 82; and it is possible to practice the invention using just onesleeve 128 and one trocar 132, or just one sleeve 130 and one trocar132. In such a situation, the sleeve element would serve to retain thebone block in position within the bone tunnel while the trocar isreplaced by the rod which will ultimately hold the bone block to thebone.

It should also be appreciated that the present application will haveutility with respect to setting cross-pins which may not necessarily beabsorbable. In particular, the present invention will have utilitywherever cross-pinning needs to be achieved for cross-pins which cannotbe passed directly through the bone and/or bone block, e.g., where thecross-pins may be too soft or too brittle or too fragile to passdirectly through the bone and/or bone block, or where the cross-pins mayhave a geometry which makes it difficult or impossible for them to bepassed directly through the bone and/or bone block. By way of example,the present invention might be used to set cross-pins made out ofplastic and/or ceramic materials, or the present invention might be usedto set cross-pins made out of metal.

In addition, numerous other alternatives are contemplated within thescope of the present invention in its broadest aspects.

More particularly, it will be understood by those skilled in the artthat there are many instances wherein it is desired to locate a portionof a piece of soft tissue, such as a ligament, tendon or the like,within a bone tunnel, without a bone block attached to it. This mayoccur, for example, where a prosthetic substitute for a ligament, tendonor the like is to be used to effect a repair, or in those instanceswherein it is undesirable for one reason or another to harvest a repairgraft from elsewhere in the patient's body along with a bone blocknaturally attached to one end of the graft.

In such cases, a portion of the piece of tissue alone may becross-pinned in a bone tunnel by any of the methods discussed above.Specifically, as shown in FIGS. 41 and 42, the portion 150 of the pieceof tissue 152 to be cross-pinned in the bone tunnel is preferably foldedback upon itself one or more times. When this is done, tacking stitches154 may be used to hold the layers 156 of folded tissue together whilethe resulting mass 150 is inserted or pulled into the bone tunnel in amanner similar to the procedures used to locate a bone block in a bonetunnel discussed above. Thereafter, cross-pinning proceeds substantiallyas discussed above, such that the rods 158 ultimately extend eitherthrough the tissue mass (see phantom lines in FIG. 41), or between thefolded tissue layers (see phantom lines in FIG. 42), or both.

In this alternative, the chances of the rod and/or sleeve and/or trocartearing laterally out of, or longitudinally along, the tissue 152 may besignificant. This is particularly the case in those instances whereinthe repair is to be subjected to substantial stress prior to completehealing. Accordingly, it is often desirable to reinforce the portion 150of the tissue 152 to be cross-pinned within the bone tunnel. This may beaccomplished in numerous ways well known to those skilled in the art.One such alternative, representatively shown in FIG. 43, is to “whipstitch” the portion 150 of the tissue 152 which is to be cross-pinnedwithin the bone tunnel. This creates a braid-enclosed, substantiallysolid mass 160 adapted to receive the rods 158, and adds the strength ofthe numerous passes of the cord-like material 162, extending through thetissue as used to form the “whip stitch”, to alleviate the tear-outproblem referred to above. In addition, “whip stitching” is wellunderstood by surgeons, and relatively easy to do. Therefore, thisalternative avoids certain complications which may arise during theharvesting of tissue grafts with bone blocks attached; avoids trimmingbone blocks to fit bone tunnels during surgical procedures; and providesa simple, fast and efficient way to cross-pin the tissue in a bonetunnel, with minimal added trauma to the patient.

As noted above, the foregoing procedures may also be used to secureartificial grafts in the bone tunnel, i.e., grafts comprising anartificial prosthetic device not harvested from the body. In such acase, it may or may not be desirable to fold the graft back upon itselfone or more times, in the manner shown in FIGS. 41-43, prior tocross-pinning.

Similarly, a portion 150 of a piece of tissue 152 may be fixed in a bonetunnel by positioning a bio-absorbable rod 163 diametrically across thebone tunnel 164, and thereafter pulling the portion 150 of the piece oftissue 152 into an open end of the bone tunnel, around the rod 163 andback out the same open end of the bone tunnel. More particularly, asbest seen in FIGS. 44-51, it has been found that the positioning of abio-absorbable rod 163 diametrically across bone tunnel 164 is bestaccomplished with a trocar/sleeve combination 171 such as thatillustratively shown in FIGS. 15-17. This is because in any alternativewherein a means such as a sharpened k-wire, trocar or the like is usedwithout an accompanying sleeve to form an opening through the bone 166,through the bone tunnel 164, and into the bone 166 on the opposite sideof the bone tunnel 164, it is difficult to remove the hole-formingdevice and to replace it with a rod 163. Typically, the rod 163 willpass through the opening 168 (FIG. 49) and through the bone tunnel 164easily, however, it is often not as easy to locate and engage opening170 on the other side of bone tunnel 164 with the forward end of rod163.

Accordingly, in the practice of this alternative, it is preferred that atrocar/sleeve combination 171 be drilled in the manner discussed indetail above into bone 166, transversely to the longitudinal axis 172(FIG. 44) of bone tunnel 164, diametrically through bone tunnel 164, andinto bone 166 on the opposite side of bone tunnel 164 (see FIGS. 44 and45). Thereafter, the trocar 171 a is removed from sleeve 171 b, and abio-absorbable rod 163 is inserted into sleeve 171 a so as to occupy aposition extending across bone tunnel 164 (see FIGS. 46-48). Sleeve 171b is then removed from bone 166 and rod 163, leaving rod 163 extendingfrom opening 168, diametrically across bone tunnel 164 and into opening170 (see FIG. 49).

At this point in the procedure, or earlier if desired, one end 175 of alength of cord-like material, such as suture 173, is secured to an end174 of piece of tissue 152 (FIG. 50). The other end 176 of the length ofcord-like material 173 is then threaded into an open end 178 of bonetunnel 164, and thence around rod 163, and then back out open end 178 ofbone tunnel 164 (see FIG. 50). Finally, the free end 176 of thecord-like material 173 is pulled so as to draw portion 150 of piece oftissue 152 into open end 178 of bone tunnel 164, around bio-absorbablerod 163, and back out open end 178 of bone tunnel 164. Tissue portion150 thus assumes a generally U-shape, having its closed end slidablysecured in bone tunnel 164 by bio-absorbable rod 163, and its free endsextending outwardly from the same open end 178 of bone tunnel 164 (seeFIG. 51).

As noted above, the foregoing procedure may also be used to secureartificial grafts in the bone tunnel, i.e., grafts comprising anartificial prosthetic device not harvested from the body.

Still further, it has been found that, in practice, bone blocks arerelatively hard. This is frequently the case where the bone block isformed out of cortical bone. In addition, it can also sometimes berelatively difficult to drill a trocar/sleeve combination through bone166, particularly where bone 166 comprises a substantial layer ofcortical bone.

Consequently, it can be difficult to drill a trocar/sleeve combination(see, for example, FIG. 55) through the bone, and into and/or throughthe bone block. In addition, even if this drilling is successfullyaccomplished, the bone block may fracture, as shown, for example, inFIGS. 52 and 53. In this respect it is noted that the possibility ofbone block fracture may be reduced by reducing the diameter of thetrocar/sleeve combination, and hence the resulting hole through the boneblock, but this may in turn lead to an increase in the possibility ofrod breakage when a load is applied to the graft ligament.

Two alternatives have been developed to address these problems.

In the first of these alternatives, best seen in FIG. 54, the solutionutilizes the facts that (1) a bone block is significantly stronger incompression than it is in tension, and (2) a larger diameter rod willprovide a stronger bone block fixation in a bone tunnel if bone blockfracture is not an issue. Specifically, the bone block 200 is located atsubstantially closed end 202 of substantially blind bone tunnel 204,with its associated tissue graft 206 extending outwardly from the openend 208 of the substantially blind bone tunnel 204. It will beunderstood that a guide hole 201 may extend through substantially closedend 202 of bone tunnel 204 so as to allow bone block 200 to be drawninto bone tunnel 204 by a cord-like element 203, or otherwise located inbone tunnel 204 as discussed hereinabove. A rod 208, as much as 30%larger in diameter than a rod suitable for emplacement through boneblock 200, is then located diametrically across bone tunnel 204 adjacentto proximal end 210 of bone block 200. In this case, rod 208 ispositioned utilizing the same method as described above with regard tothe threading of a portion of a piece of tissue over a rod extendingdiametrically through a bone tunnel (see FIGS. 44-51). Also, the rod 208may pass through the tissue graft 208, or not, as desired. The result isthat bone block 200 is reliably fixed in bone tunnel 206 betweensubstantially closed tunnel end 202 and rod 208.

The second of the above-mentioned alternatives proceeds from the premisethat if the sleeve does not have to extend into or through the boneblock, a significantly larger diameter rod may be used with acorresponding increase in the strength of the fixation of the bone blockin the bone tunnel. This alternative is representatively shown in FIGS.56-63, which will be referred to specifically below.

In this case, the trocar/sleeve combinations 210 (see FIGS. 15-17 and55) are drilled through the skin and into the bone in the same manner asdiscussed in detail above, and the bone block is located in the bonetunnel such that the various elements reside in a configurationgenerally as depicted in FIG. 22. At this point, the trocars aredisengaged from the sleeves, the bone block is pulled up into the bonetunnel (FIG. 23), and rods are inserted through (i) the sleeves and (ii)the bone located between the distal ends of the sleeves and the bonetunnel, and then into the bone block.

The latter insertion step may be accomplished in any one of severaldifferent ways. For example, a second, longer trocar 212 a, 212 b may beinserted into each of the sleeves 214 a, 214 b and either drilled (FIG.57) or tapped (FIG. 58) through the bone 216 located between the distalends 218 a, 218 b of the sleeves 214 a, 214 b and then into the bonetunnel 220 and into the bone block 222. Thereafter, one of the longertrocars 212 is removed (FIG. 59), and a metal, plastic, ceramic orbio-absorbable rod 224 a is inserted into the bone and the bone blockthrough the sleeve (FIG. 60). This is followed by the removal of theother longer trocar 212 (FIG. 61) and the insertion of another rod 224 binto the bone and bone block through the second sleeve (FIG. 62).Finally, the sleeves are removed from the patient (FIG. 63).

In the last discussed alternative, the longer trocars 212 a and 212 bare commonly stepped, e.g., in the manner shown in FIG. 24. Moreparticularly, the longer trocars 212 a commonly include a distal portion230 having a smaller transverse cross-sectional diameter than theirproximal portion 232, and define a distally-facing radial shoulder 234at the joiner of their proximal and distal portions. In this way, theextent of trocar penetration beyond the distal ends of the sleeves iscontrolled by pre-selecting the axial length of the distal portion ofthe longer trocars. More specifically, the longer trocars are allowed topenetrate beyond the distal ends of the sleeves only to the point atwhich their distally-facing radial shoulders engage either the bone atthe distal ends of the sleeves, or a radially-disposed, inwardprojection 236 formed on the sleeve side wall (FIG. 65).

Alternatively, rigid rods 224 a, 224 b may be driven through the sleeves214 a, 214 bthrough the bone 216 located between the sleeves and thebone tunnel 220, and then into the bone block 222 directly. This may beaccomplished by, preferably, pointing or rounding the distal ends of therods 224 a, 224 binserting the rods into the sleeves 214 a, 214 bandusing a plunger shaft 238 and tapping means 240 to drive the rods intoposition through the bone and into the bone block (FIG. 66).

It further has been found, that in the interlocking trocar/sleeveassembly shown in FIGS. 15-17 and 55, the radial shoulder 242 (FIG. 55),formed by the distal end of the sleeve proximally of the pointed distalend 224 of the trocar extending distally thereof, can be a significantimpediment to the passage of the interlocked trocar/sleeve combinationinto bone. Indeed, in practice, this shoulder, while normally only about0.005 to 0.010 inch in radial thickness, has been noted to cause burningof the bone as the trocar/sleeve combination is advanced through thebone toward the bone tunnel. To correct this problem, the distal edge242 of the sleeve could be bevelled at an angle substantially equal tothat of the adjacent trocar point 244 (see FIG. 67). This is notpreferred, however, in view of the variations in machining tolerancecommonly acceptable in the art in the formation of bevelled edges andtrocar points. In particular, the chance of an exact mating of thetrocar point with a bevelled sleeve end is unlikely. Hence, the boneburning problem, and more generally the problem of the resistance topenetration of the trocar/sleeve combination into the bone, are stillpresent in the embodiment shown in FIG. 67, albeit to a perhaps smallerdegree than in the FIG. 55 embodiment.

To solve this basic problem, it has been found that the distal end 246of the sleeve 248 should be slanted at an angle of approximately 15°proximally relative to a plane 250 located normal to the longitudinalaxis 252 of the sleeve (see FIG. 68). In the resulting construction ofthe trocar/sleeve assembly, the trocar point 256 drills into the bone inthe same manner as previously described, while the slanted distal end246 of the sleeve 248 cuts into the sidewall of the hole formed by thetrocar point, instead of rotating flat against the bone surrounding thehole being formed by the trocar. As a practical matter, this alternativeis deemed to be of significant importance, inasmuch as the ease of useof the methods and apparatus described herein affects their commercialutility. A bone drill which does not exhibit a tendency to bind, and/orto burn the bone during use, is significantly more desirable than a bonedrill which does bind or burn the bone during use.

Accordingly it will be understood that, currently, one preferred methodof practicing the present invention includes the following steps:

(1) drilling at least two trocar/sleeve assemblies, of the type depictedin FIG. 68, into the bone to a position similar to that shown in FIG. 22(note: this may be accomplished by sequentially and separately mating asingle trocar with each sleeve and drilling that assembly into thebone);

(2) removing the trocar(s) from the sleeves so as to leave the sleevesextending through the skin and into the bone, but not intersecting thebone tunnel;

(3) removing the rack assembly (see element 52 in FIG. 21) from thesleeves and the bone tunnel;

(4) locating a bone block in the bone tunnel in alignment with axialprojections of the sleeves;

(5) using a first, elongated, stepped trocar (see FIG. 64) to drillthrough the bone between the distal end of the first sleeve and the bonetunnel, through the bone block, and a pre-selected distance into thebone on the opposite side of the bone tunnel;

(6) with the first, elongated stepped trocar extending through the boneand the bone block, using a second, elongated stepped trocar to drillthrough the bone between the distal end of the second sleeve and thebone tunnel, through the bone block, and a pre-selected distance intothe bone on the opposite side of the bone tunnel;

(7) removing the second trocar from the bone, the bone block and thesecond sleeve;

(8) inserting a rigid rod (of bio-absorbable, or non-bio-absorbable,material) through the second sleeve to a position wherein it extendsthrough the bone block and engages openings on opposite sides of thebone tunnel as formed by the second elongated stepped trocar;

(9) removing the first trocar from the bone, the bone block and thefirst sleeve;

(10) inserting another rigid rod (of bio-absorbable, ornon-bio-absorbable, material) through the first sleeve to a positionwherein it extends through the bone block and engages the openings onopposite sides of the bone tunnel as formed by the first elongatedstepped trocar; and

(11) removing the first and second sleeves from the patient.

The last mentioned alternatives also provide advantageous settings forthe use of certain modifications to the above-described cross-pinningapparatus. For example, in the embodiment of the rack assembly discussedabove wherein the cannulated sleeve 58 has an enlarged head 62 adaptedfor location in a bone tunnel transversely of the trocar/sleeveassemblies which are being drilled into the surrounding bone (FIGS.19-21), a flattened head 258 (FIG. 69) defining a window 260therethrough might be used in place of the enlarged head 62. In such acase, the flattened head 258 would extend substantially diametricallyacross the bone tunnel 262 in a plane transverse to an axial projectionof the trocar/sleeve assemblies 264 being drilled into the bone.Further, the window 260 would be so disposed that the trocar/sleeveassemblies (or the trocars alone) could penetrate into the bone tunnel,through the window 260 in the head of the cannulated sleeve 266, andthen into the bone on the opposite side of the bone tunnel.

More particularly, as shown in FIG. 69, this embodiment of the presentinvention is useful in any situation in which it is desired to formdiametrically opposed openings in the sidewall of a bone tunnel.Particular examples of such situations include those wherein the lengthof the sleeve and the length, and rigidity, of the rods are such thatthey may be relied upon to ensure that a rod entering the bone tunnelfrom the drill means entry side thereof will be maintained in alignmentwith, and engage, the opening on the other side of the bone tunnel.Thus, those cases mentioned above wherein a rigid rod is passed throughan object in a bone tunnel may find this alternative beneficial.

Finally, it is to be understood that the interlocking trocar/sleeveassemblies discussed hereinabove have numerous other uses beyond thecross-pinning of objects in bone tunnels. One such illustrative use isin the placement of absorbable, or non-absorbable, pins across bonefractures so as to assist in maintaining broken bones in a desiredhealing relationship after fracture reduction procedures have beencompleted. As depicted in FIGS. 70-74, this method follows the nowwell-understood steps of drilling a trocar/sleeve assembly into thedesired position in bone, removing the trocar, inserting a rod into thesleeve, and then removing the sleeve from the bone and the rod.

Other illustrative uses of the devices and concepts of the presentinvention may include, among others, the removal of tissue from theinterior of bones, and/or the delivery of other things into the interiorof a bone, such as other devices or prostheses, drugs, bone graftmaterial, substitute bone marrow, and so on.

Numerous further variations, alterations, modifications and otherderivations of the present invention will occur and/or become obvious tothose skilled in the art in view of the foregoing detailed descriptionof the preferred embodiments of the present invention. Accordingly, itis to be understood that the foregoing specification and the appendeddrawings are intended to be illustrative only, and not as limiting ofthe invention.

What is claimed is:
 1. A method for fixing a portion of a piece oftissue in a bone tunnel in a bone, the method comprising the steps of:placing the portion of a piece of tissue in the bone tunnel; advancingspaced-apart, first and second drill means through the bone transverselyof the bone tunnel so as to intersect and extend into the tissue;removing one of the drill means and replacing the one removed drillmeans with a first rod; and removing the other of the drill means andreplacing the other removed drill means with a second rod; whereby toretain the portion of a piece of tissue in the bone tunnel with saidrods.
 2. A method according to claim 1 wherein said drill means areadvanced completely through the said portion of said piece of tissue. 3.A method according to claim 1 wherein said drill means are advancedpartially through the said portion of said piece of tissue.
 4. A methodaccording to claim 1 wherein said portion of said piece of tissue isreinforced so as to resist tearing away from said drill means and saidrods.
 5. A method according to claim 4 wherein said portion of saidpiece of tissue is whip stitched with a cord-like element to providesaid reinforcement.
 6. A method according to claim 1 wherein said rodsare formed of a substantially rigid, bio-absorbable material.
 7. Amethod according to claim 6 wherein said material is selected from thegroup consisting of polylactic acid, polyglycolic acid andpolydiaxanone.
 8. The method according to claim 1 wherein said rods areformed of a material selected from the group consisting of substantiallyrigid metals, plastics and ceramics.
 9. The method according to claim 1wherein said drill means defines a tip adapted to drill through saidbone by rotation about its longitudinal axis and to pierce said portionof a piece of tissue by distal movement along a projection of itslongitudinal axis.
 10. A method according to claim 9 wherein said drillmeans are selected from the group consisting of spade drills, distallypointed wires, trocars, and substantially longitudinally flighted,distally pointed drills.
 11. A method for fixing a portion of a piece oftissue in a bone tunnel in a bone, the method comprising the steps of:placing the portion of a piece of tissue in the bone tunnel; advancing afirst drill means through a first portion of the bone and transverselyof the tunnel so as to intersect and extend into said portion of a pieceof tissue; advancing a second drill means through a second portion ofthe bone and transversely of the tunnel so as to intersect and extendinto said portion of a piece of tissue, said second drill means beingspaced from said first drill means; removing one of said first andsecond drill means while leaving the other of said first and seconddrill means in place in the bone and the portion of a piece of tissue;advancing a first rod through a bore left by removal of the one drillmeans, such that the first rod extends through the bone and into saidportion of a piece of tissue; removing the other of the first and seconddrill means; and advancing a second rod through a bore left by removalof the other drill means, such that the second rod extends through thebone and into said portion of a piece of tissue; whereby to retain saidportion of a piece of tissue in the bone tunnel with said rods.
 12. Amethod according to claim 11 wherein said drill means are advancedcompletely through the said portion of said piece of tissue.
 13. Amethod according to claim 11 wherein said drill means are advancedpartially through the said portion of said piece of tissue.
 14. A methodaccording to claim 11 wherein said portion of said piece of tissue isreinforced so as to resist tearing away from said drill means and saidrods.
 15. A method according to claim 14 wherein said portion of saidpiece of tissue is whip stitched with a cord-like element to providesaid reinforcement.
 16. A method according to claim 11 wherein said rodsare formed of a substantially rigid, bio-absorbable material.
 17. Amethod according to claim 16 wherein said material is selected from thegroup consisting of polylactic acid, polyglycolic acid andpolydiaxanone.
 18. The method according to claim 11 wherein said rodsare formed of a material selected from the group consisting ofsubstantially rigid metals, plastics and ceramics.
 19. The methodaccording to claim 11 wherein said drill means defines a tip adapted todrill through said bone by rotation about its longitudinal axis and topierce said portion of a piece of tissue by distal movement along aprojection of its longitudinal axis.
 20. A method according to claim 19wherein said drill means are selected from the group consisting of spadedrills, distally pointed wires, trocars, and substantiallylongitudinally flighted, distally pointed drills.
 21. A method forfixing a portion of a piece of tissue in a bone tunnel in a bone, themethod comprising the steps of: (a) placing the portion of a piece oftissue in the bone tunnel; (b) advancing a plurality of drill meansthrough the bone transversely of the tunnel so as to intercept andextend into said portion of a piece of tissue; (c) removing at least oneof the drill means while leaving at least one of the drill means inplace, and replacing the removed at least one drill means with at leastone rod; (d) removing at least one further of the drill means andreplacing the at least one further of the drill means with at least onefurther rod; and (e) repeating step (d), if and as desired, until aselected number of the drill means each is replaced by a rod, whereby toretain said portion a piece of tissue in the bone tunnel with said rods.22. A method according to claim 21 wherein said drill means are advancedcompletely through the said portion of said piece of tissue.
 23. Amethod according to claim 21 wherein said drill means are advancedpartially through the said portion of said piece of tissue.
 24. A methodaccording to claim 21 wherein said portion of said piece of tissue isreinforced so as to resist tearing away from said drill means and saidrods.
 25. A method according to claim 24 wherein said portion of saidpiece of tissue is whip stitched with a cord-like element to providesaid reinforcement.
 26. A method according to claim 21 wherein said rodsare formed of a substantially rigid, bio-absorbable material.
 27. Amethod according to claim 26 wherein said material is selected from thegroup consisting of polylactic acid, polyglycolic acid andpolydiaxanone.
 28. The method according to claim 21 wherein said rodsare formed of a material selected from the groups consisting ofsubstantially rigid metals, plastics and ceramics.
 29. The methodaccording to claim 21 wherein said drill means defines a tip adapted todrill through said bone by rotation about its longitudinal axis and topierce said portion of a piece of tissue by distal movement along aprojection of its longitudinal axis.
 30. A method according to claim 29wherein said drill means are selected from the group consisting of spadedrills, distally pointed wires, trocars, and substantiallylongitudinally flighted, distally pointed drills.
 31. A method forfixing a portion of a piece of tissue in a bone tunnel in a bone, saidmethod comprising the steps of: advancing first and second spaced-apartdrill means through the bone transversely of the bone tunnel so as tointersect and permissibly extend through the bone tunnel; withdrawingsaid first and second spaced-apart drill means from said bone tunnel;locating a portion of a piece of tissue in said bone tunnel intransverse alignment with the paths of said first and secondspaced-apart drill means through said bone; advancing third and fourthspaced-apart drill means into, and permissibly through, said portion ofa piece of tissue; removing the third of the drill means and replacingthe third removed drill means with a first rod; and removing the fourthof said drill means and replacing the fourth of said drill means with asecond rod; whereby to retain the portion of a piece of tissue in thebone tunnel with the rods.
 32. The method according to claim 31 whereinsaid first drill means is the same as said third drill means, and saidsecond drill means is the same as said fourth drill means.
 33. Themethod according to claim 31 wherein said first, second, third andfourth drill means are selected from the group consisting of distallypointed metal wires, trocars, spade drills, substantially longitudinallyflighted distally pointed drills, and trocar/sleeve combinations whereinthe trocar substantially fills and releasably interlocks with the sleevein a position in which the pointed distal end of the trocar extendsdistally of the distal end of the sleeve.
 34. The method according toclaim 31 wherein each of said drill means comprises a trocar/sleevecombination and wherein said removing and replacing steps compriseremoving the trocar from its associated sleeve, replacing the trocarwith a rod, and removing the sleeve from the bone and the rod.
 35. Amethod according to claim 31 wherein said drill means are advancedcompletely through the said portion of said piece of tissue.
 36. Amethod according to claim 31 wherein said drill means are advancedpartially through the said portion of said piece of tissue.
 37. A methodaccording to claim 31 wherein said portion of said piece of tissue isreinforced so as to resist tearing away from said drill means and saidrods.
 38. A method according to claim 31 wherein said portion of saidpiece of tissue is whip stitched with a cord-like element to providesaid reinforcement.
 39. A method according to claim 31 wherein said rodsare formed of a substantially rigid, bio-absorbable material.
 40. Amethod according to claim 39 wherein said material is selected from thegroup consisting of polylactic acid, polyglycolic acid andpolydiaxanone.
 41. The method according to claim 31 wherein said rodsare formed of a material selected from the group consisting ofsubstantially rigid metals, plastics and ceramics.
 42. The methodaccording to claim 31 wherein said drill means defines a tip adapted todrill through said bone by rotation about its longitudinal axis and topierce said portion of a piece of tissue by distal movement along aprojection of its longitudinal axis.